US20210280497A1 - Modular technique for die-level liquid cooling - Google Patents
Modular technique for die-level liquid cooling Download PDFInfo
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- US20210280497A1 US20210280497A1 US16/810,341 US202016810341A US2021280497A1 US 20210280497 A1 US20210280497 A1 US 20210280497A1 US 202016810341 A US202016810341 A US 202016810341A US 2021280497 A1 US2021280497 A1 US 2021280497A1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/46—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids
- H01L23/473—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids by flowing liquids
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/46—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/02—Containers; Seals
- H01L23/04—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls
- H01L23/053—Containers; Seals characterised by the shape of the container or parts, e.g. caps, walls the container being a hollow construction and having an insulating or insulated base as a mounting for the semiconductor body
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
- H01L23/373—Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
- H01L23/3735—Laminates or multilayers, e.g. direct bond copper ceramic substrates
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L25/00—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof
- H01L25/03—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes
- H01L25/04—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers
- H01L25/065—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L27/00
- H01L25/0655—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L27/00 the devices being arranged next to each other
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L25/00—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof
- H01L25/03—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes
- H01L25/04—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers
- H01L25/065—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L27/00
- H01L25/0657—Stacked arrangements of devices
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2225/00—Details relating to assemblies covered by the group H01L25/00 but not provided for in its subgroups
- H01L2225/03—All the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/648 and H10K99/00
- H01L2225/04—All the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/648 and H10K99/00 the devices not having separate containers
- H01L2225/065—All the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/648 and H10K99/00 the devices not having separate containers the devices being of a type provided for in group H01L27/00
- H01L2225/06503—Stacked arrangements of devices
- H01L2225/06589—Thermal management, e.g. cooling
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
- H01L23/373—Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
- H01L23/3736—Metallic materials
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/40—Mountings or securing means for detachable cooling or heating arrangements ; fixed by friction, plugs or springs
- H01L23/4006—Mountings or securing means for detachable cooling or heating arrangements ; fixed by friction, plugs or springs with bolts or screws
Definitions
- MCPs multi-chip packages
- MC-DRAM multi-chip dynamic random access memory
- IHS integrated heat spreader
- a lid over the die (e.g., a silicon die or dice).
- a thermal solution such as a passive heat sink, a heat sink/fan combination or liquid cooling solution.
- TIM thermal interface material
- FIG. 1 shows a cross-sectional and schematic side view of an embodiment of an integrated circuit chip assembly that includes a thermal solution.
- FIG. 2A shows a top perspective view of a die including channels operable to be attached to a die having active devices and circuitry as part of a thermal solution.
- FIG. 2B shows a top perspective view of another embodiment of a die including channels therein operable to be attached to a die having active devices and circuitry offering a thermal solution.
- FIG. 3 shows a top perspective view of the die of FIG. 2A following the formation of a thermally conductive material.
- FIG. 4 shows a top perspective view of an embodiment of a die including active devices and circuits processed to receive the die of FIG. 3 by the formation of a conductive material on a backside of the die.
- FIG. 5 shows the connecting of the die of FIG. 3 to the die of FIG. 4 .
- FIG. 6 shows the assembly including the connected dice of FIG. 3 and FIG. 4 .
- FIG. 7 provides a flow chart of a method of forming an assembly including a die with channels therein connected to a die with active devices and circuits.
- FIG. 8 shows another embodiment of an assembly including a die including channels connected to a die with active devices and circuitry formed therein for a fluid cooling solution.
- FIG. 9 shows a cross-sectional side view of another embodiment of an assembly offering a thermal solution.
- FIG. 10 shows a cross-sectional side view of another embodiment of an assembly offering a thermal solution.
- FIGS. 11A-11D show cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution.
- FIG. 12 is a flowchart showing operations in an embodiment of a method of fabricating an assembly offering a thermal solution.
- FIGS. 13A-13C show cross-sectional side views of embodiments of an assembly offering a thermal solution.
- FIGS. 14A-14D shows cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution.
- FIG. 15 illustrates an embodiment of a computing device.
- FIG. 1 shows a cross-sectional and schematic side view of an embodiment of an apparatus that includes a thermal solution.
- die 105 that is, for example, a logic die (e.g., a processor) formed from a semiconductor material platform connected to substrate 115 such as a package substrate.
- die 105 has device side 106 including a number of contacts to transistor devices and circuits in a device layer and backside 107 opposite device side 106 .
- Device side 106 is connected to substrate 115 (e.g., a package substrate) through, for example, solder connections 125 .
- die 120 is a semiconductor material (e.g., silicon) that is not an active die (e.g., does not include any active devices formed in a device layer, where an active device is a device capable of controlling electrical current by means of an electrical signal.
- Die 120 includes a body and a number of laterally disposed channels formed in the body of the die. In this embodiment, the laterally disposed channels extend into and out of the page through a depth portion of die 120 , including an entire portion of the depth of the die or substantially the entire portion of the depth of the die (e.g., 70 percent, 80 percent or 90 percent).
- the channels extending across a width of die 120 (defined by an x-dimension) over a portion including an entire portion or substantially the entire portion of the width dimension of the die (e.g., 70 percent, 80 percent or 90 percent).
- the channels extend across an area of die 120 requiring thermal management, such as an area encompassed by backside 107 of die 105 .
- a portion of the channels, including an active portion alternately bring a cooling fluid toward die 105 and take heated fluid away from die 105 for the purpose of heat transfer.
- backside 107 of die 105 is connected to die 120 through a thermally conductive material.
- each of backside 107 of die 105 and a mating side of die 120 have a thermally conductive material such as a copper material (e.g., a copper layer and/or copper nanorods) and the dies are connected through a conductive material bond (e.g., a copper-copper bond).
- each die includes a barrier layer on which the thermally conductive material (e.g., copper) is disposed.
- die 105 and die 120 each have a thickness on the order of 600 microns ( ⁇ m) to 900 ⁇ m.
- FIG. 1 An inset of FIG. 1 shows a magnified view of a portion of interface 140 of die 105 and die 120 .
- interface 140 includes barrier layer 1401 formed on surface 107 of die 105 .
- Barrier layer 1401 is, for example, a titanium material having a representative thickness on the order of about 100 nanometers (nm).
- adhesive layer 1402 Disposed directly on barrier layer 1401 is adhesive layer 1402 of, for example, a nitride material (e.g., titanium nitride). In one embodiment, adhesive layer 1402 has a thickness on the order of 250 nm.
- a thermally conductive material such as copper (e.g., a copper layer and/or nanorods).
- a mating side of die 120 similarly includes barrier layer 1406 disposed on a surface of die 120 .
- Barrier layer 1406 is representatively a titanium material having a thickness on the order of 100 nm.
- adhesive layer 1407 Disposed directly on barrier layer 1406 is adhesive layer 1407 of, for example, titanium nitride having a thickness on the order of 250 nm.
- a thermally conductive material such as copper (e.g., copper layer and/or nanorods).
- interface 140 includes thermally conductive material interface 1408 having a representative thickness on the order of 1 ⁇ m to 3 ⁇ m. There is no conventional thermal interface material (TIM) between die 120 and die 105 .
- TIM thermal interface material
- Manifold 130 Overlaying die 120 in the assembly of FIG. 1 is manifold 130 .
- Manifold 130 includes inlet 142 configured to introduce a fluid into a body of manifold 130 and outlet 150 configured to remove fluid from a body of manifold 130 .
- Distributor assembly 145 includes, in one embodiment, a number of distributors having openings in fluid communication with a portion of channels in die 120 including, in one embodiment, each of the channels.
- collector assembly 155 in one embodiment, includes a number of collectors wherein respective ones of the collectors are in fluid communication with a portion of the channels in die 120 , including, in one embodiment, each of the channels.
- a fluid e.g., liquid or gas
- a fluid is configured to be introduced through inlet 142 , to flow through distributor assembly 145 , through a body of manifold 130 and into channels of die 120 .
- the fluid generally travels through the channels to a base thereof and then out of the channels.
- the fluid travelling out of the channels travels through the body of manifold 130 and is collected in collector assembly 155 and removed from manifold 130 through outlet 150 .
- Manifold 130 representatively is a glass material with inlet 142 , outlet 150 , distributor assembly 145 and collector assembly 155 formed therein.
- Manifold 130 has an area that covers an area of die 120 including the channels therein. In one embodiment, an area of manifold 130 is similar to an area of die 120 . In one embodiment, there is no conventional TIM between manifold 130 and die 120 .
- apparatus 100 also includes a feedback loop to circulate cooling fluid and control its temperature.
- a level of coolant is stored in reservoir 181 .
- a suitable coolant is, for example, water.
- Another coolant is propendiol.
- Other coolants may also be suitable.
- Fluid flow from reservoir 181 to manifold 130 is driven by pump 183 .
- An optional chiller 182 may be placed downstream of reservoir 181 .
- pump 183 is controlled by controller 185 which is, for example, a pulse-width-modulation controller connected to an H-bridge. Downstream of pump 183 is optional flow filter 187 and flow meter 188 .
- Flow meter 188 in one embodiment, is monitorable and controllable.
- Flow regime control is assisted with, for example, an H-bridge, that provides the capability to reverse the pump motor direction and apply braking/deceleration to quickly change a flow rate.
- Pulse-width-modulation input to a pump motor allows for precise control of the pump speed for flow rate control.
- a speed of pump 183 can be increased to provide additional cooling.
- the pump speed may be decreased to target or maintain a constant die temperature.
- a temperature of the cooling fluid is measured by temperature gauge 190 that is, for example, a thermocouple.
- Components described with respect to the representative feedback loop may be positioned above manifold 130 or in an area away from manifold 130 (e.g., on another area of package substrate 115 ). In the configuration where a representative feedback loop is positioned in an area away from manifold 130 , tubing may be used to bring fluid to inlet 142 and from outlet 150 .
- FIG. 2A shows a top perspective view of a die including channels (e.g., micro-channels) as part of a thermal solution.
- Die 220 is, in one embodiment, a semiconductor material (e.g., single crystal silicon).
- Die 220 includes a number of laterally disposed channels (channels 2205 , 2210 and 2215 identified) formed in a body of the die. Such channels may be formed, for example, by a lithographic and etch operations or by a laser drilling operation.
- each channel (e.g., channels 2205 , 2210 and 2215 ) has a width, w, on the order of 50 microns ( ⁇ m) to 200 ⁇ m and, in this embodiment, extends in a z-direction through the body of die 220 .
- each channel has a depth, d, substantially through the body of die 220 (e.g., 70 percent through the body, 80 percent through the body, 90 percent through the body).
- the channels extend across an x-direction width of die 220 .
- such channels are exposed at a top surface of die 220 as viewed.
- each channel (channels 2205 , 2210 and 2215 ) has a rectangular profile. It is appreciated that such profile is dependent upon the fabrication conditions and does not necessarily have to be rectangular.
- each channel may have a rounded base and/or the sidewalls may not be parallel.
- FIG. 2B shows a top perspective view of another embodiment of a die offering a thermal solution.
- die 220 B includes channels disposed within a body of the die and in a z-direction through the body of the die. Such channels may be formed by, for example, an etch or laser drilling process and depositing a cap layer of a thermally conductive material such as a semiconductor material on the top to close the required openings. Access to the channels for a manifold assembly to provide a fluid to the channels may be provided by lithographic and etch operations to form desired openings.
- FIGS. 3-6 illustrate a process of forming an assembly including an active die (e.g., logic die (e.g., central processing unit (CPU)) and a secondary die that provides a thermal solution for the assembly flowchart of a method.
- FIG. 7 provides a flow chart of a method.
- FIG. 3 shows die 220 that is, for example, a secondary die or thermal solution for the assembly.
- Die 220 is similar to the die shown in FIG. 2A and includes a number of laterally disposed channels extending it in a z-direction across the die. Such channels and the processes described in FIGS. 3-6 may be formed at a wafer level where die 220 is one of a number of designated dice formed in a similar manner.
- channels 2205 , 2210 and 2215 of another channel are formed in the die by lithographic and etch operations or by laser drilling (block 710 , FIG. 7 ).
- a backside of the die is processed (block 720 , FIG. 7 ).
- the process includes forming barrier layer 221 of, for example, titanium having a thickness on the order of 100 nanometers (nm) across a surface of the die.
- adhesive layer 222 is formed.
- adhesive layer 222 is a nitride such as titanium nitride deposited across a surface of the die having a representative thickness on the order of 250 nm.
- a thermally conductive material may be formed on a die.
- a thermally conductive material includes copper layer 223 and copper nanorods 224 .
- copper layer 223 may be formed by an electroplating process such as by seeding a surface of die 220 (an exposed surface of adhesive layer 222 ) with a seed material and then plating copper layer 223 across the surface.
- Nanorods 224 may also be plated thereon. Including nanorods 224 provides the functionality of low temperature bonding and compensation for any y-dimension height mismatch.
- a masking layer may be initially applied over copper layer 223 then opening may be formed in the masking layer at locations for the nanorods.
- Nanorods 224 may then be plated into copper layer 223 and then the masking layer removed.
- only nanorods are plated by, for example, seeding an exposed surface of adhesive layer with a seed material, masking the surface, forming openings through the masking a nanorod locations, plating nanorods and then removing the masking and excess seed material.
- only a copper layer (copper layer 223 ) is plated.
- FIG. 4 shows an embodiment of a top perspective view of an embodiment of a die including active devices and circuits process to receive the die of FIG. 3 .
- FIG. 4 shows die 205 that is, for example, a logic or other die (e.g., a memory die) including device layer 2052 of a number of active devices and circuitry. Die 205 may be formed according to conventional processes at a wafer level. Once formed, die 205 is processed to accept a secondary die such as die 220 offering thermal solution at a singulated die or wafer level.
- a logic or other die e.g., a memory die
- thermally conductive material such as copper.
- thermally conductive material includes layer 208 of, for example, electroplated copper and nanorods 209 formed as described above (block 715 , FIG. 7 ).
- FIG. 5 shows the connecting of die 220 to die 205 .
- die 220 is positioned so that a backside of die 220 including the thermally conductive material (copper layer 223 and/or nanorods 224 ), in this embodiment, is facing a similar thermally conductive material on die 205 .
- the two dice are aligned and thermally bonded together (block 725 , FIG. 7 ).
- FIG. 6 shows the assembly including the connected die 205 and die 220 .
- the connection forms interface 240 of the thermally conductive material on the surface of each die. If processed at a wafer level for each die, following the connection (e.g., thermal bonding) of the dice, the two wafers may be singulated to produce a separate composite structure or assembly as shown in FIG. 6 .
- FIG. 8 shows another embodiment of an assembly including a thermal solution of a die having channels (e.g., micro-channels or micro-jets) formed therein for a fluid cooling solution.
- assembly 400 includes active die 405 that is, for example, a logic die such as CPU. Overlaying die 405 is die 420 that includes a thermal solution of, for example, channels formed therein. Die 405 and die 420 may be connected (connected on a backside or non-device side of logic die 405 ) by interface 440 of a thermally conductive material such as copper as described above.
- a device side of die 405 is connected to substrate 415 such as a package substrate or printed circuit board by, for example, solder connections (e.g., a ball grid array).
- Die 420 includes, in one embodiment, a number of a laterally disposed channels as described above. In one embodiment, the channels are exposed on a surface of the die (similar to FIG. 2A ). Disposed on die 420 , in this embodiment, is manifold 430 . Manifold 430 includes therein a distributor assembly and a collector assembly. Distributor assembly 445 includes, in one embodiment, a number of distributors having openings in fluid communication with a portion of the channels in die 420 (e.g., all of the channels) and collector assembly 455 , in one embodiment, includes a number of collectors wherein the respective ones of the collectors are also in fluid communication with a portion of the channels in die 420 . The distributors that make up distributor assembly 445 are connected to inlet 441 and collectors that make up collector assembly 455 are connected to outlet 450 A or outlet 450 B.
- support 475 is connected to the assembly of die 420 and die 405 .
- support 475 is connected to the assembly through substrate 415 by support screws 480 .
- Support 475 has an area dimension larger than the individual die (e.g., 30 percent larger, 50 percent larger) so as to cover a surface of manifold 430 and die 420 and die 405 between the support and substrate 415 .
- inlet pipe 485 e.g., plastic tubing
- outlet pipe 490 A and outlet pipe 490 B Disposed in support 475 is inlet pipe 485 (e.g., plastic tubing) and outlet pipe 490 A and outlet pipe 490 B.
- the inlet pipes and outlet pipes through support 475 are aligned with inlet 441 and outlets 450 A and 450 B of manifold 430 , respectively.
- fluid such as water
- inlet 485 fluid, such as water
- distributor assembly 445 in manifold 430 and into channels of die 420 .
- collector assembly 455 in manifold 430 and is removed through outlet 450 A or outlet 450 B into outlet pipe 490 A and outlet pipe 490 B, respectively.
- the assembly of FIG. 8 may include a feedback loop such as described above with reference to FIG. 1 to circulate cooling fluid and control as temperature.
- FIG. 9 shows a cross-sectional side view of another embodiment of an assembly offering a thermal solution.
- die 505 that is, for example, logic die or CPU having a device layer wherein the device layer is connected to substrate 515 such as a package substrate or printed circuit board.
- substrate 515 such as a package substrate or printed circuit board.
- die 520 Disposed on a backside of die 505 is die 520 that provides a thermal solution in the form of a number of channels formed as described above.
- Die 505 and die 520 are connected to one another through interface 540 of a thermally conductive material such as copper.
- manifold 530 Disposed on a surface of die 520 (a top surface as viewed) is manifold 530 of, for example, a glass material.
- distributor assembly 545 including, in one embodiment, a number of distributors having an openings in fluid communication with a portion of the channels in die 520 (e.g., all of the channels in die 520 ).
- collector assembly 555 including a number of collectors, wherein the respective ones of the collectors are in fluid communication with a portion of the channels in die 520 .
- Distributors that make up distributor assembly 545 are connected to inlet 542 and collectors that make up collector assembly 555 are connected to outlet 550 .
- IHS integrated heat spreader
- IHS integrated heat spreader
- IHS 575 completely surrounds the assembly of die 505 , die 520 and manifold 530 . In this manner, the assembly is encased within IHS 575 . In one embodiment, there is no TIM between IHS 575 and manifold 530 or between manifold 530 and die 520 . As viewed, inlet 542 and outlet 550 extend from manifold 530 through IHS 575 . Accordingly, a fluid may be introduced through inlet 542 at a surface of IHS 575 (a top surface, as viewed) and through manifold 530 and die 520 and return to outlet 550 through IHS 575 .
- the assembly of FIG. 9 may include a feedback loop such as described above with reference to FIG. 1 to circulate cooling fluid and control as temperature.
- FIG. 10 shows a cross-sectional side view of another embodiment of an assembly including a multi-chip package (MCP).
- MCP multi-chip package
- FIG. 10 shows a first assembly including die 505 A that is, for example, an active die connected to die 520 A that has a thermal solution of, for example, micro-channels or micro-jets as described above; die 505 B that has an active die connected to die 520 B that includes a thermal solution; and die 505 C connected to die 520 C that includes a thermal solution.
- Dice 505 A, 505 B and 505 C may each be a logic die (e.g., a processor) or other functional die (e.g., a memory die).
- Each of a device side of die 505 A, die 505 B and die 505 C is connected to substrate 515 (e.g., a package substrate) through, for example, solder connections.
- substrate 515 e.g., a package substrate
- Overlaying each of die 520 A, die 520 B and die 520 C is a manifold.
- FIG. 10 shows manifold 530 A on die 520 A, manifold 530 B on die 520 B, and manifold 530 C on die 520 C.
- Each manifold representatively includes a distributor assembly and a collector assembly as described above.
- IHS 575 Overlaying the three dice in the multi-chip package assembly is IHS 575 of, for example, a thermally conductive material. In this embodiment, IHS 575 completely surrounds or encompasses the three dice. In one embodiment, there is no TIM between the manifolds and IHS 575 or between the manifolds and dice 520 A- 520 C, respectively.
- FIG. 10 shows inlet 542 connected to manifold 530 A.
- Inlet 542 is configured to deliver a fluid such as water to manifold 530 A and the distributor assembly therein.
- the fluid flows through the micro-channels or micro-jets of die 520 A and into a collector assembly of manifold 530 A. From the collector assembly, the fluid moves through outlet 545 A.
- outlet 545 A also serves as an inlet to the assembly including die 505 B and die 520 B.
- Outlet 545 A is connected as an inlet to manifold 530 B and fluid flows into manifold 530 B, through the distributor assembly therein and into the micro-channels or micro-jets of die 520 B and is collected through the collector assembly therein.
- the collector assembly in manifold 530 B transfers the fluid to outlet 545 B.
- Outlet 545 B in this embodiment, also serves as the inlet to the assembly including die 505 C and die 520 C.
- Outlet 545 B delivers fluid to manifold 530 C.
- the fluid travels through the distributor assembly therein and is collected through the collector assembly and release through outlet 550 .
- Outlet 550 is disposed through IHS 575 .
- embodiments of the present disclosure are directed to fabrication of a dielectric interface, e.g., as an alternative to interface 140 of die 105 and die 120 described above in FIG. 1 .
- FIGS. 11A-11D show cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution.
- FIG. 12 is a flowchart 1200 showing operations in an embodiment of a method of fabricating an assembly offering a thermal solution.
- an active silicon die (or wafer of dies) 1102 and a silicon die (or wafer of dies) 1104 are provided for bonding.
- the silicon die 1104 has a plurality of fluidly accessible channels 1106 therein.
- one or both of the active silicon die 1102 and the silicon die 1104 may be subjected to grinding to a target thickness. In other embodiments, the active silicon die 1102 and the silicon die 1104 are not subjected to grinding. In either case, the thickness of each of the active silicon die 1102 and/or the silicon die 1104 may be in a range of approximately 100-800 microns.
- one or both of the active silicon die 1102 and the silicon die 1104 may be cleaned, e.g., by wet cleaning and/or plasma cleaning.
- a first dielectric layer 1108 is deposited on a backside of the active silicon die 1102 , the backside opposite a device side of the active silicon die 1102 .
- a second dielectric layer 1110 may be deposited on the silicon die 1104 .
- the first dielectric layer 1108 and/or the second dielectric layer 1110 are deposited by physical vapor deposition (PVD) or plasma enhanced chemical vapor deposition (PECVD).
- first dielectric layer 1108 and the second dielectric layer 1110 is composed of a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- each of the first dielectric layer 1108 and the second dielectric layer 1110 is formed to a thickness in the range of 50-150 nanometers.
- both the active silicon die 1102 and the silicon die 1104 have a dielectric layer deposited thereon. In an alternative embodiment, only one of the active silicon die 1102 and the silicon die 1104 has a dielectric layer deposited thereon.
- an outgassing operation may be performed for one or both of the first dielectric layer 1108 and the second dielectric layer 1110 .
- the outgassing operation involves heating to a sufficient temperature to remove trapped gases, such as but not limited to hydrogen or ammonia, in the one or both of the first dielectric layer 1108 and the second dielectric layer 1110 .
- the heating is at a temperature less than or equal to 300 degrees Celsius, or more preferably, less than or equal to 200 degrees Celsius.
- the heating is at or greater than a temperature used for subsequent bonding (e.g., operation 1212 of flowchart 1200 ) of the first dielectric layer 1108 and the second dielectric layer 1110 .
- the outgassing densifies the first dielectric layer 1108 and/or the second dielectric layer 1110 .
- the first dielectric layer 1108 and/or the second dielectric layer 1110 are planarized by a chemical mechanical planarization (CMP) process.
- CMP chemical mechanical planarization
- the first dielectric layer 1108 and/or the second dielectric layer 1110 is planarized to a surface roughness less than 0.5 nm Ra (average roughness) or less than 0.5 nm Rq (peak roughness).
- the first dielectric layer 1108 and/or the second dielectric layer 1110 is reduced by a thickness in an amount in the range of 5-50 nanometers during the planarizing. Referring to operation 1210 of flowchart 1200 , the first dielectric layer 1108 and the second dielectric layer 1110 may be activated and cleaned.
- the first dielectric layer 1108 and/or the second dielectric layer 1110 are exposed to a plasma activation process.
- the plasma activation process involves exposing the film to a plasma based on O2, N2, Ar, or a combination thereof, at standard atmospheric pressure and at room temperature.
- the first dielectric layer 1108 and/or the second dielectric layer 1110 are then rinsed with deionized (DI) water or a standard clean is performed.
- DI deionized
- the surface of both layers is a hydrophillic surface.
- the first dielectric layer 1108 is contacted to and then bonded to the second dielectric layer 1110 .
- the bonding forms interface dielectric 1108 / 1110 between the active silicon die (or wafer of dies) 1102 and a silicon die (or wafer of dies) 1104 .
- contacting the first dielectric layer 1108 to the second dielectric layer 1110 involves atomic forces between the first dielectric layer 1108 and the second dielectric layer 1110 .
- bonding the first dielectric layer 1108 to the second dielectric layer 1110 involves heating the first dielectric layer 1108 and the second dielectric layer 1110 .
- the heating is at a temperature less than or equal to 300 degrees Celsius, or more preferably, less than or equal to 200 degrees Celsius. In an embodiment, the heating is performed at a temperature in the range of 200-300 degrees Celsius.
- the dielectric interface 1108 / 1110 has an interfacial thermal resistance of less than approximately 0.002 C ⁇ cm2/W.
- die pairings may be singulated from the wafers 1102 and 1104 , e.g., by a dicing process.
- Each die pairing includes a first silicon die 1102 A having a device side and a backside opposite the device side.
- a second silicon die 1104 A includes a plurality of fluidly accessible channels 1106 therein.
- a dielectric interface 1108 / 1110 directly couples the second silicon die 1104 A to the backside of the first silicon die 1102 A.
- the fluidly accessible channels 1106 may be coupled to an inlet 1120 and an outlet 1122 , as is depicted.
- the dicing may provide a same footprint for first silicon die 1102 A (active) and the second silicon die 1104 A (microchannel die).
- FIGS. 13A-13C show cross-sectional side views of embodiments of an assembly offering a thermal solution.
- a die pairing 1300 includes a first silicon die 1302 having a device side and a backside opposite the device side.
- a second silicon die 1304 (such as a die having a plurality of fluidly accessible channels therein) is coupled directly to the backside of the first silicon die 1302 by a dielectric interface 1306 .
- the dielectric interface 1306 includes a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx). As illustrated in FIG. 13A , there is no seam within the dielectric interface 1306 . In an embodiment, there are no additional thermal interface materials and/or epoxy adhesives between the first silicon die 1302 and the second silicon die 1304 .
- a die pairing 1320 includes a first silicon die 1322 having a device side and a backside opposite the device side.
- a second silicon die 1324 (such as a die having a plurality of fluidly accessible channels therein) is coupled directly to the backside of the first silicon die 1322 by a dielectric interface 1326 .
- the dielectric interface 1326 includes a seam 1330 therein.
- the dielectric interface 1326 is a bilayer having a first layer 1328 A and a second layer 1328 B.
- the first layer 1328 A includes a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx)
- the second layer 1328 B includes a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- the SiOx in the case of a layer of silicon oxide (SiOx), the SiOx is a native oxide on a silicon surface, a grown oxide layer (e.g., thermal oxide), or a deposited layer (e.g., a plasma enhanced chemical vapor deposition, PECVD, layer).
- first layer 1328 A and the second layer 1328 B of the bilayer have a same composition. In an embodiment, the first layer 1328 A and the second layer 1328 B of the bilayer have a same thickness. In an embodiment, there are no additional thermal interface materials and/or epoxy adhesives between the first silicon die 1322 and the second silicon die 1324 . However, in other embodiments, e.g., where both the first layer 1328 A and the second layer 1328 B are silicon nitride (SiN), plasma treatment can create a thin oxide at the interface of the first layer 1328 A and the second layer 1328 B in place of seam 1330 at the location of the dashed line.
- SiN silicon nitride
- both the first layer 1328 A and the second layer 1328 B are silicon carbonitride (SiCN)
- plasma treatment can create a thin SiCOxNy layer at the interface of the first layer 1328 A and the second layer 1328 B in place of seam 1330 at the location of the dashed line.
- first layer 1328 A and the second layer 1328 B of the bilayer have a different composition. In an embodiment, the first layer 1328 A and the second layer 1328 B of the bilayer have a different thickness. In an embodiment, there are no additional thermal interface materials and/or epoxy adhesives between the first silicon die 1322 and the second silicon die 1324 .
- one of the first layer 1328 A and the second layer 1328 B is silicon nitride (SiN) and the other of the first layer 1328 A and the second layer 1328 B is silicon carbonitride (SiCN).
- one of the first layer 1328 A and the second layer 1328 B is silicon nitride (SiN) and the other of the first layer 1328 A and the second layer 1328 B is silicon oxide (SiOx).
- one of the first layer 1328 A and the second layer 1328 B is silicon oxide (SiOx) and the other of the first layer 1328 A and the second layer 1328 B is silicon carbonitride (SiCN).
- a die pairing 1340 includes a first silicon die 1342 having a device side and a backside opposite the device side.
- a second silicon die 1344 (such as a die having a plurality of fluidly accessible channels therein) is coupled directly to the backside of the first silicon die 1342 by a dielectric interface 1346 .
- the dielectric interface 1346 includes a seam 1350 therein.
- the dielectric interface 1346 is a bilayer having a first layer 1348 A and a second layer 1348 B.
- At least one of the first layer 1348 A or the second layer 1348 B of the bilayer is composed of silicon oxide (SiOx) having a plurality of nanovoids 1352 therein (shown for layer 1348 A in this case, but could instead or in addition be for layer 1348 B).
- SiOx silicon oxide
- FIGS. 14A-14D shows cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution.
- an active silicon die 1404 is provided on a substrate 1402 , such as a package substrate, a silicon interposer, an active interposer (any of which may be in the form of a wafer level package), or a temporary carrier substrate.
- substrate 1402 is a package substrate
- active silicon die may be flip chip bonded to pads of the package substrate.
- An underfill material may be between the active silicon die 1404 and the package substrate 1402 and along portions of the sidewalls of the active silicon die 1404 .
- the active silicon die 1404 is overmolded with a mold compound 1406 , as depicted in FIG. 14B . Referring to FIG.
- the mold compound 1406 is grinded to form mold compound 1406 A and to expose the backside of the silicon die 1404 .
- mold compound 1406 A is on the package substrate 1402 and laterally surrounding the first active silicon die 1404 .
- grinding the mold compound forms concave regions 1408 in the mold compound 1406 A.
- a dielectric layer 1410 is then formed on the backside of the silicon die 1404 and on the mold compound 1406 A, as is depicted in FIG. 14D . In the case of the formation of concave regions 1408 , the dielectric layer 1410 may be formed in the concave regions 1408 in the mold compound 1406 A.
- a second die 1412 is then bonded to the active silicon die 1404 .
- the dielectric layer 1410 can be used as a dielectric interface, or a portion of a dielectric interface, between the second die 1412 and the active silicon die 1404 .
- the dielectric layer 1410 is planarized by a chemical mechanical planarization (CMP) process prior to bonding the second die 1412 and the active silicon die 1404 .
- CMP chemical mechanical planarization
- substrate 1402 may be removed and build-up layers may be formed on the resulting exposed active side of the active silicon die 1404 and on the mold compound 1406 A, e.g., to provide one or more routing layers having a fan out arrangement.
- a wafer level package architecture may similarly be fabricated where, e.g., active silicon die 1402 is instead a microchannel die or wafer.
- active silicon die 1402 is instead a microchannel die or wafer.
- the molded die or wafer includes through silicon vias (TSVs)
- TSVs through silicon vias
- the above process can be performed before TSV reveal or after TSV reveal.
- the process may be performed at wafer level and at relatively low temperature.
- FIG. 15 illustrates a computing device 1500 in accordance with one implementation.
- Computing device 1500 houses board 1502 .
- Board 1502 may include a number of components, including but not limited to processor 1504 and at least one communication chip 1506 .
- Processor 1504 is physically and electrically coupled to board 1502 .
- at least one communication chip 1506 is also physically and electrically coupled to board 1502 .
- communication chip 1506 is part of processor 1504 .
- computing device 1500 may include other components that may or may not be physically and electrically coupled to board 1502 .
- these other components include, but are not limited to, volatile memory (e.g., DRAM), non-volatile memory (e.g., ROM), flash memory, a graphics processor, a digital signal processor, a crypto processor, a chipset, an antenna, a display, a touchscreen display, a touchscreen controller, a battery, an audio codec, a video codec, a power amplifier, a global positioning system (GPS) device, a compass, an accelerometer, a gyroscope, a speaker, a camera, and a mass storage device (such as hard disk drive, compact disk (CD), digital versatile disk (DVD), and so forth).
- volatile memory e.g., DRAM
- non-volatile memory e.g., ROM
- flash memory e.g., a graphics processor, a digital signal processor, a crypto processor, a chipset, an antenna
- Communication chip 1506 enables wireless communications for the transfer of data to and from computing device 1500 .
- wireless and its derivatives may be used to describe circuits, devices, systems, methods, techniques, communications channels, etc., that may communicate data through the use of modulated electromagnetic radiation through a non-solid medium. The term does not imply that the associated devices do not contain any wires, although in some embodiments they might not.
- Communication chip 1506 may implement any of a number of wireless standards or protocols, including but not limited to Wi-Fi (IEEE 802.11 family), WiMAX (IEEE 802.16 family), IEEE 802.20, long term evolution (LTE), Ev-DO, HSPA+, HSDPA+, HSUPA+, EDGE, GSM, GPRS, CDMA, TDMA, DECT, Bluetooth, derivatives thereof, as well as any other wireless protocols that are designated as 3G, 4G, 5G, and beyond.
- Computing device 1500 may include a plurality of communication chips 1506 .
- first communication chip 1506 may be dedicated to shorter range wireless communications such as Wi-Fi and Bluetooth and second communication chip 1506 may be dedicated to longer range wireless communications such as GPS, EDGE, GPRS, CDMA, WiMAX, LTE, Ev-DO, and others.
- Processor 1504 of computing device 1500 includes an integrated circuit die packaged within processor 1504 .
- the integrated circuit die of the processor 1504 may include or be part of a thermal solution such as described above.
- the term “processor” may refer to any device or portion of a device that processes electronic data from registers and/or memory to transform that electronic data into other electronic data that may be stored in registers and/or memory.
- Communication chip 1506 also includes an integrated circuit die packaged within communication chip 1506 .
- the integrated circuit die of the communication chip 1506 may include or be part of a thermal solution such as described above.
- another component housed within computing device 1500 may contain an integrated circuit die that may include or be part of a thermal solution such as described above.
- computing device 1500 may be a laptop, a netbook, a notebook, an ultrabook, a smartphone, a tablet, a personal digital assistant (PDA), an ultra mobile PC, a mobile phone, a desktop computer, a server, a printer, a scanner, a monitor, a set-top box, an entertainment control unit, a digital camera, a portable music player, or a digital video recorder.
- computing device 1500 may be any other electronic device that processes data.
- An integrated circuit assembly includes a first silicon die comprising a device side and a backside opposite the device side.
- the integrated circuit assembly also includes a second silicon die comprising a plurality of fluidly accessible channels therein.
- a dielectric interface directly couples the second silicon die to a backside of the first silicon die.
- Example embodiment 2 The integrated circuit assembly of example embodiment 1, wherein the dielectric interface comprises a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- the dielectric interface comprises a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- Example embodiment 3 The integrated circuit assembly of example embodiment 1 or 2, wherein the dielectric interface comprises a seam therein.
- Example embodiment 4 The integrated circuit assembly of example embodiment 1, wherein the dielectric interface is a bilayer having a first layer comprising a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx), and having a second layer comprising a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- the dielectric interface is a bilayer having a first layer comprising a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx)
- SiN silicon nitride
- SiCN silicon carbonitride
- SiOx silicon oxide
- Example embodiment 5 The integrated circuit assembly of example embodiment 4, wherein the first layer and the second layer of the bilayer have a same composition.
- Example embodiment 6 The integrated circuit assembly of example embodiment 4, wherein the first layer and the second layer of the bilayer have a different composition.
- Example embodiment 7 The integrated circuit assembly of example embodiment 4, 5 or 6, wherein at least one of the first layer or the second layer of the bilayer comprises silicon oxide (SiOx) having a plurality of nanovoids therein.
- SiOx silicon oxide
- Example embodiment 8 The integrated circuit assembly of example embodiment 1, 2, 3, 4, 5, 6 or 7, further comprising a lid disposed on the second silicon die, the lid comprising an area dimension that covers an area comprising the channels.
- Example embodiment 9 The integrated circuit assembly of example embodiment 8, wherein the lid comprises a fluid inlet and a fluid outlet.
- An integrated circuit assembly includes at least one package including a first silicon die comprising a device side and a backside opposite the device side, a second silicon die coupled directly to the backside of the first silicon die by a dielectric interface, the second silicon die comprising a plurality of channels therein and a fluid inlet operable to deliver a fluid to the plurality of channels and a fluid outlet.
- the integrated circuit assembly also includes a package substrate coupled to the device side of the first silicon die.
- Example embodiment 11 The integrated circuit assembly of example embodiment 10, wherein the dielectric interface comprises a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- the dielectric interface comprises a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- Example embodiment 12 The integrated circuit assembly of example embodiment 10 or 11, wherein the dielectric interface comprises a seam therein.
- Example embodiment 13 The integrated circuit assembly of example embodiment 10, 11 or 12, wherein the at least one package further comprises a lid disposed on the second die, the lid comprising an area dimension that covers an area comprising the channels.
- Example embodiment 14 The integrated circuit assembly of example embodiment 13, wherein the lid comprises the fluid inlet and the fluid outlet.
- Example embodiment 15 The integrated circuit assembly of example embodiment 10, 11, 12, 13 or 14, further including a mold compound on the package substrate and laterally surrounding the first silicon die.
- Example embodiment 16 The integrated circuit assembly of example embodiment 15, wherein the dielectric interface is further on the mold compound.
- Example embodiment 17 The integrated circuit assembly of example embodiment 15, wherein the mold compound has concave regions therein.
- Example embodiment 18 The integrated circuit assembly of example embodiment 17, wherein the dielectric interface is further in the concave regions of the mold compound.
- Example embodiment 19 A method of fabricating an integrated circuit assembly includes depositing a first dielectric layer on a backside of a first silicon die, the backside opposite a device side of the first silicon die. A second dielectric layer is deposited on a second silicon die, the second silicon die comprising a plurality of fluidly accessible channels therein.
- the first dielectric layer is bonded directly to the second dielectric layer.
- Example embodiment 20 The method of example embodiment 19, wherein depositing the first dielectric layer or the second dielectric layer comprises depositing by physical vapor deposition (PVD) or plasma enhanced chemical vapor deposition (PECVD).
- PVD physical vapor deposition
- PECVD plasma enhanced chemical vapor deposition
- Example embodiment 21 The method of example embodiment 20, further comprising performing an outgassing process subsequent to depositing by the plasma enhanced chemical vapor deposition (PECVD) and prior to bonding the first dielectric layer directly to the second dielectric layer.
- PECVD plasma enhanced chemical vapor deposition
- Example embodiment 22 The method of example embodiment 19, 20 or 21, further including planarizing the first dielectric layer or the second dielectric layer by a chemical mechanical planarization (CMP) process prior to bonding the first dielectric layer directly to the second dielectric layer.
- CMP chemical mechanical planarization
- Example embodiment 23 The method of example embodiment 19, 20, 21 or 22, wherein bonding the first dielectric layer directly to the second dielectric layer comprises exposing the first dielectric layer and the second dielectric layer to a plasma activation process, rinsing the first dielectric layer and the second dielectric layer with deionized (DI) water, contacting the first dielectric layer to the second dielectric layer, and heating the first dielectric layer to the second dielectric layer.
- DI deionized
- Example embodiment 24 The method of example embodiment 23, wherein the heating is performed at a temperature in the range of 200-300 degrees Celsius.
- Example embodiment 25 The method of example embodiment 19, 20, 21, 22, 23 or 24, further including, prior to depositing the first dielectric layer on the backside of the first silicon die, overmolding the first silicon die with a mold compound, and grinding the mold compound to expose the backside of the first silicon die, wherein grinding the mold compound comprises forming concave regions in the mold compound.
- Depositing the first dielectric layer on the backside of the first silicon die further comprises depositing the first dielectric layer on the mold compound and in the concave regions in the mold compound, and the method further includes planarizing the first dielectric layer by a chemical mechanical planarization (CMP) process prior to bonding the first dielectric layer directly to the second dielectric layer.
- CMP chemical mechanical planarization
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Abstract
Description
- Thermal management for integrated circuit devices.
- Decreasing feature sizes and increasing package densities are making thermal issues important in integrated circuit related products, particularly high power products such as server products. The total thermal design power is increasing with respect to generation which demands that cross-plane heat removal be improved. Still further, the emergence of multi-chip packages (MCPs) in, for example, high-power servers where, for example, multi-chip dynamic random access memory (MC-DRAM) stacked packages currently generate approximately nine watts to 10 watts of power and come coated with die backside film polymeric layers that present a high thermal resistance that is difficult to compensate for with traditional air cooling.
- Many high-power central processing unit (CPU) products use an integrated heat spreader (IHS) as a lid over the die (e.g., a silicon die or dice). Onto this lid mounts a thermal solution, such as a passive heat sink, a heat sink/fan combination or liquid cooling solution. Limitations of these configurations include a relatively large stack-up height and multiple thermal interfaces where thermal interface material (TIM) must be applied. Thermal performance of TIM materials have been optimized yet a need still remains to improve the thermal management of high-power microprocessors.
-
FIG. 1 shows a cross-sectional and schematic side view of an embodiment of an integrated circuit chip assembly that includes a thermal solution. -
FIG. 2A shows a top perspective view of a die including channels operable to be attached to a die having active devices and circuitry as part of a thermal solution. -
FIG. 2B shows a top perspective view of another embodiment of a die including channels therein operable to be attached to a die having active devices and circuitry offering a thermal solution. -
FIG. 3 shows a top perspective view of the die ofFIG. 2A following the formation of a thermally conductive material. -
FIG. 4 shows a top perspective view of an embodiment of a die including active devices and circuits processed to receive the die ofFIG. 3 by the formation of a conductive material on a backside of the die. -
FIG. 5 shows the connecting of the die ofFIG. 3 to the die ofFIG. 4 . -
FIG. 6 shows the assembly including the connected dice ofFIG. 3 andFIG. 4 . -
FIG. 7 provides a flow chart of a method of forming an assembly including a die with channels therein connected to a die with active devices and circuits. -
FIG. 8 shows another embodiment of an assembly including a die including channels connected to a die with active devices and circuitry formed therein for a fluid cooling solution. -
FIG. 9 shows a cross-sectional side view of another embodiment of an assembly offering a thermal solution. -
FIG. 10 shows a cross-sectional side view of another embodiment of an assembly offering a thermal solution. -
FIGS. 11A-11D show cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution. -
FIG. 12 is a flowchart showing operations in an embodiment of a method of fabricating an assembly offering a thermal solution. -
FIGS. 13A-13C show cross-sectional side views of embodiments of an assembly offering a thermal solution. -
FIGS. 14A-14D shows cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution. -
FIG. 15 illustrates an embodiment of a computing device. -
FIG. 1 shows a cross-sectional and schematic side view of an embodiment of an apparatus that includes a thermal solution.FIG. 1 shows die 105 that is, for example, a logic die (e.g., a processor) formed from a semiconductor material platform connected tosubstrate 115 such as a package substrate. In this embodiment, die 105 hasdevice side 106 including a number of contacts to transistor devices and circuits in a device layer andbackside 107opposite device side 106.Device side 106 is connected to substrate 115 (e.g., a package substrate) through, for example,solder connections 125. - Connected to
backside 107 of die 105 is die 120 or secondary die 120. In one embodiment, die 120 is a semiconductor material (e.g., silicon) that is not an active die (e.g., does not include any active devices formed in a device layer, where an active device is a device capable of controlling electrical current by means of an electrical signal. Die 120 includes a body and a number of laterally disposed channels formed in the body of the die. In this embodiment, the laterally disposed channels extend into and out of the page through a depth portion of die 120, including an entire portion of the depth of the die or substantially the entire portion of the depth of the die (e.g., 70 percent, 80 percent or 90 percent).FIG. 1 also shows the channels extending across a width of die 120 (defined by an x-dimension) over a portion including an entire portion or substantially the entire portion of the width dimension of the die (e.g., 70 percent, 80 percent or 90 percent). In one embodiment, the channels extend across an area of die 120 requiring thermal management, such as an area encompassed bybackside 107 of die 105. As will be explained later, a portion of the channels, including an active portion, alternately bring a cooling fluid toward die 105 and take heated fluid away from die 105 for the purpose of heat transfer. - In one embodiment,
backside 107 of die 105 is connected to die 120 through a thermally conductive material. In one embodiment, each ofbackside 107 of die 105 and a mating side of die 120 have a thermally conductive material such as a copper material (e.g., a copper layer and/or copper nanorods) and the dies are connected through a conductive material bond (e.g., a copper-copper bond). In one embodiment, each die includes a barrier layer on which the thermally conductive material (e.g., copper) is disposed. Representatively, die 105 and die 120 each have a thickness on the order of 600 microns (μm) to 900 μm. - An inset of
FIG. 1 shows a magnified view of a portion ofinterface 140 of die 105 and die 120. In this embodiment,interface 140 includesbarrier layer 1401 formed onsurface 107 of die 105.Barrier layer 1401 is, for example, a titanium material having a representative thickness on the order of about 100 nanometers (nm). Disposed directly onbarrier layer 1401 isadhesive layer 1402 of, for example, a nitride material (e.g., titanium nitride). In one embodiment,adhesive layer 1402 has a thickness on the order of 250 nm. Disposed onadhesive layer 1402 is a thermally conductive material such as copper (e.g., a copper layer and/or nanorods). A mating side of die 120 similarly includesbarrier layer 1406 disposed on a surface of die 120.Barrier layer 1406 is representatively a titanium material having a thickness on the order of 100 nm. Disposed directly onbarrier layer 1406 isadhesive layer 1407 of, for example, titanium nitride having a thickness on the order of 250 nm. Disposed onadhesive layer 1407 is a thermally conductive material such as copper (e.g., copper layer and/or nanorods). When die 105 and die 120 are joined,interface 140 includes thermallyconductive material interface 1408 having a representative thickness on the order of 1 μm to 3 μm. There is no conventional thermal interface material (TIM) between die 120 and die 105. - Overlaying die 120 in the assembly of
FIG. 1 ismanifold 130. Manifold 130 includesinlet 142 configured to introduce a fluid into a body ofmanifold 130 andoutlet 150 configured to remove fluid from a body ofmanifold 130. Disposed within a body ofmanifold 130 isdistributor assembly 145 andcollector assembly 155.Distributor assembly 145 includes, in one embodiment, a number of distributors having openings in fluid communication with a portion of channels in die 120 including, in one embodiment, each of the channels. Similarly,collector assembly 155, in one embodiment, includes a number of collectors wherein respective ones of the collectors are in fluid communication with a portion of the channels indie 120, including, in one embodiment, each of the channels. The distributors that make updistributor assembly 145 are connected to theinlet 142 and the collectors that make upcollector assembly 155 are connected tooutlet 150. Accordingly, in one embodiment, a fluid (e.g., liquid or gas) is configured to be introduced throughinlet 142, to flow throughdistributor assembly 145, through a body ofmanifold 130 and into channels ofdie 120. The fluid generally travels through the channels to a base thereof and then out of the channels. The fluid travelling out of the channels travels through the body ofmanifold 130 and is collected incollector assembly 155 and removed frommanifold 130 throughoutlet 150.Manifold 130 representatively is a glass material withinlet 142,outlet 150,distributor assembly 145 andcollector assembly 155 formed therein.Manifold 130 has an area that covers an area ofdie 120 including the channels therein. In one embodiment, an area ofmanifold 130 is similar to an area ofdie 120. In one embodiment, there is no conventional TIM betweenmanifold 130 and die 120. - Referring again to
FIG. 1 ,apparatus 100, in one embodiment, also includes a feedback loop to circulate cooling fluid and control its temperature. Representatively, a level of coolant is stored inreservoir 181. A suitable coolant is, for example, water. Another coolant is propendiol. Other coolants may also be suitable. Fluid flow fromreservoir 181 tomanifold 130 is driven bypump 183. Anoptional chiller 182 may be placed downstream ofreservoir 181. In one embodiment, pump 183 is controlled bycontroller 185 which is, for example, a pulse-width-modulation controller connected to an H-bridge. Downstream ofpump 183 isoptional flow filter 187 and flowmeter 188.Flow meter 188, in one embodiment, is monitorable and controllable. Flow regime control is assisted with, for example, an H-bridge, that provides the capability to reverse the pump motor direction and apply braking/deceleration to quickly change a flow rate. Pulse-width-modulation input to a pump motor allows for precise control of the pump speed for flow rate control. As heat flux increases fromdie 105 and consequently the die temperature increases, a speed ofpump 183 can be increased to provide additional cooling. Likewise, as the die heat flux decreases, the pump speed may be decreased to target or maintain a constant die temperature. A temperature of the cooling fluid is measured bytemperature gauge 190 that is, for example, a thermocouple. Components described with respect to the representative feedback loop may be positioned abovemanifold 130 or in an area away from manifold 130 (e.g., on another area of package substrate 115). In the configuration where a representative feedback loop is positioned in an area away frommanifold 130, tubing may be used to bring fluid toinlet 142 and fromoutlet 150. -
FIG. 2A shows a top perspective view of a die including channels (e.g., micro-channels) as part of a thermal solution.Die 220 is, in one embodiment, a semiconductor material (e.g., single crystal silicon).Die 220 includes a number of laterally disposed channels (channels channels die 220. Preferably, each channel has a depth, d, substantially through the body of die 220 (e.g., 70 percent through the body, 80 percent through the body, 90 percent through the body). In this embodiment, the channels extend across an x-direction width ofdie 220. As illustrated, such channels are exposed at a top surface ofdie 220 as viewed. As illustrated, each channel (channels -
FIG. 2B shows a top perspective view of another embodiment of a die offering a thermal solution. In this embodiment, die 220B includes channels disposed within a body of the die and in a z-direction through the body of the die. Such channels may be formed by, for example, an etch or laser drilling process and depositing a cap layer of a thermally conductive material such as a semiconductor material on the top to close the required openings. Access to the channels for a manifold assembly to provide a fluid to the channels may be provided by lithographic and etch operations to form desired openings. -
FIGS. 3-6 illustrate a process of forming an assembly including an active die (e.g., logic die (e.g., central processing unit (CPU)) and a secondary die that provides a thermal solution for the assembly flowchart of a method.FIG. 7 provides a flow chart of a method. Referring toFIG. 3 andFIG. 7 ,FIG. 3 shows die 220 that is, for example, a secondary die or thermal solution for the assembly.Die 220 is similar to the die shown inFIG. 2A and includes a number of laterally disposed channels extending it in a z-direction across the die. Such channels and the processes described inFIGS. 3-6 may be formed at a wafer level where die 220 is one of a number of designated dice formed in a similar manner. Once the channels are formed, the individual die may be singulated or such singulation may occur after the dice are assembled onto an active or logic die. Referring toFIG. 3 , as an initial operation,channels FIG. 7 ). Following the fabrication of the channels, a backside of the die (a side opposite the open channels) is processed (block 720,FIG. 7 ). In one embodiment, the process includes formingbarrier layer 221 of, for example, titanium having a thickness on the order of 100 nanometers (nm) across a surface of the die. Following the formation ofbarrier layer 221,adhesive layer 222 is formed. In one embodiment,adhesive layer 222 is a nitride such as titanium nitride deposited across a surface of the die having a representative thickness on the order of 250 nm. - Following the formation of
adhesive layer 222, a thermally conductive material may be formed on a die. In one embodiment, a thermally conductive material includescopper layer 223 andcopper nanorods 224. In one embodiment,copper layer 223 may be formed by an electroplating process such as by seeding a surface of die 220 (an exposed surface of adhesive layer 222) with a seed material and then platingcopper layer 223 across the surface.Nanorods 224 may also be plated thereon. Includingnanorods 224 provides the functionality of low temperature bonding and compensation for any y-dimension height mismatch. To plate nanorods oncopper layer 223, a masking layer may be initially applied overcopper layer 223 then opening may be formed in the masking layer at locations for the nanorods.Nanorods 224 may then be plated intocopper layer 223 and then the masking layer removed. In another embodiment, only nanorods are plated by, for example, seeding an exposed surface of adhesive layer with a seed material, masking the surface, forming openings through the masking a nanorod locations, plating nanorods and then removing the masking and excess seed material. In still another embodiment, only a copper layer (copper layer 223) is plated. -
FIG. 4 shows an embodiment of a top perspective view of an embodiment of a die including active devices and circuits process to receive the die ofFIG. 3 .FIG. 4 shows die 205 that is, for example, a logic or other die (e.g., a memory die) includingdevice layer 2052 of a number of active devices and circuitry.Die 205 may be formed according to conventional processes at a wafer level. Once formed, die 205 is processed to accept a secondary die such as die 220 offering thermal solution at a singulated die or wafer level.FIG. 4 shows a backside ofdie 205 includingbarrier layer 206 of, for example, a titanium material having a representative thickness on the order of 100 nm andbarrier layer 207 of a nitride material such as titanium nitride having a representative thickness on the order of 250 nm. Disposed onadhesive layer 207 is a thermally conductive material such as copper. In this embodiment, thermally conductive material includeslayer 208 of, for example, electroplated copper andnanorods 209 formed as described above (block 715,FIG. 7 ). -
FIG. 5 shows the connecting ofdie 220 to die 205. In one embodiment, done at, for example, a wafer level, die 220 is positioned so that a backside ofdie 220 including the thermally conductive material (copper layer 223 and/or nanorods 224), in this embodiment, is facing a similar thermally conductive material ondie 205. The two dice are aligned and thermally bonded together (block 725,FIG. 7 ).FIG. 6 shows the assembly including the connecteddie 205 and die 220. In this embodiment, the connection forms interface 240 of the thermally conductive material on the surface of each die. If processed at a wafer level for each die, following the connection (e.g., thermal bonding) of the dice, the two wafers may be singulated to produce a separate composite structure or assembly as shown inFIG. 6 . -
FIG. 8 shows another embodiment of an assembly including a thermal solution of a die having channels (e.g., micro-channels or micro-jets) formed therein for a fluid cooling solution. Referring toFIG. 8 ,assembly 400 includesactive die 405 that is, for example, a logic die such as CPU. Overlaying die 405 is die 420 that includes a thermal solution of, for example, channels formed therein.Die 405 and die 420 may be connected (connected on a backside or non-device side of logic die 405) byinterface 440 of a thermally conductive material such as copper as described above. A device side ofdie 405 is connected tosubstrate 415 such as a package substrate or printed circuit board by, for example, solder connections (e.g., a ball grid array).Die 420 includes, in one embodiment, a number of a laterally disposed channels as described above. In one embodiment, the channels are exposed on a surface of the die (similar toFIG. 2A ). Disposed ondie 420, in this embodiment, is manifold 430.Manifold 430 includes therein a distributor assembly and a collector assembly.Distributor assembly 445 includes, in one embodiment, a number of distributors having openings in fluid communication with a portion of the channels in die 420 (e.g., all of the channels) andcollector assembly 455, in one embodiment, includes a number of collectors wherein the respective ones of the collectors are also in fluid communication with a portion of the channels indie 420. The distributors that make updistributor assembly 445 are connected toinlet 441 and collectors that make upcollector assembly 455 are connected tooutlet 450A oroutlet 450B. - In this embodiment, connected to the assembly of
die 420 and die 405 issupport 475. In one embodiment,support 475 is connected to the assembly throughsubstrate 415 by support screws 480.Support 475, in one embodiment, has an area dimension larger than the individual die (e.g., 30 percent larger, 50 percent larger) so as to cover a surface ofmanifold 430 and die 420 and die 405 between the support andsubstrate 415. Disposed insupport 475 is inlet pipe 485 (e.g., plastic tubing) andoutlet pipe 490A andoutlet pipe 490B. The inlet pipes and outlet pipes throughsupport 475 are aligned withinlet 441 andoutlets manifold 430, respectively. The interface of the inlet and outlet pipes with the inlet and the outlets of the manifold are sealed by, for example, O-rings 418. In this embodiment, fluid, such as water, is introduced intoinlet 485. The fluid flows throughdistributor assembly 445 inmanifold 430 and into channels ofdie 420. The fluid then flows throughcollector assembly 455 inmanifold 430 and is removed throughoutlet 450A oroutlet 450B intooutlet pipe 490A andoutlet pipe 490B, respectively. The assembly ofFIG. 8 may include a feedback loop such as described above with reference toFIG. 1 to circulate cooling fluid and control as temperature. -
FIG. 9 shows a cross-sectional side view of another embodiment of an assembly offering a thermal solution. Referring toFIG. 9 , the figure shows die 505 that is, for example, logic die or CPU having a device layer wherein the device layer is connected tosubstrate 515 such as a package substrate or printed circuit board. Disposed on a backside ofdie 505 is die 520 that provides a thermal solution in the form of a number of channels formed as described above.Die 505 and die 520 are connected to one another throughinterface 540 of a thermally conductive material such as copper. Disposed on a surface of die 520 (a top surface as viewed) ismanifold 530 of, for example, a glass material. Disposed withinmanifold 530 isdistributor assembly 545 including, in one embodiment, a number of distributors having an openings in fluid communication with a portion of the channels in die 520 (e.g., all of the channels in die 520). Also disposed inmanifold 530 iscollector assembly 555 including a number of collectors, wherein the respective ones of the collectors are in fluid communication with a portion of the channels indie 520. Distributors that make updistributor assembly 545 are connected toinlet 542 and collectors that make upcollector assembly 555 are connected tooutlet 550. Disposed overmanifold 530, in this embodiment, is integrated heat spreader (IHS) 575 of, for example, a thermally conductive material which is a metal. In one embodiment,IHS 575 completely surrounds the assembly ofdie 505, die 520 andmanifold 530. In this manner, the assembly is encased withinIHS 575. In one embodiment, there is no TIM betweenIHS 575 and manifold 530 or betweenmanifold 530 and die 520. As viewed,inlet 542 andoutlet 550 extend frommanifold 530 throughIHS 575. Accordingly, a fluid may be introduced throughinlet 542 at a surface of IHS 575 (a top surface, as viewed) and throughmanifold 530 and die 520 and return tooutlet 550 throughIHS 575. The assembly ofFIG. 9 may include a feedback loop such as described above with reference toFIG. 1 to circulate cooling fluid and control as temperature. -
FIG. 10 shows a cross-sectional side view of another embodiment of an assembly including a multi-chip package (MCP). In this embodiment, an MCP is illustrated including three different die assemblies connected to the same package.FIG. 10 shows a firstassembly including die 505A that is, for example, an active die connected to die 520A that has a thermal solution of, for example, micro-channels or micro-jets as described above; die 505B that has an active die connected to die 520B that includes a thermal solution; and die 505C connected to die 520C that includes a thermal solution.Dice die 505A, die 505B and die 505C is connected to substrate 515 (e.g., a package substrate) through, for example, solder connections. Overlaying each ofdie 520A, die 520B and die 520C is a manifold.FIG. 10 shows manifold 530A ondie 520A, manifold 530B ondie 520B, and manifold 530C ondie 520C. Each manifold representatively includes a distributor assembly and a collector assembly as described above. Overlaying the three dice in the multi-chip package assembly isIHS 575 of, for example, a thermally conductive material. In this embodiment,IHS 575 completely surrounds or encompasses the three dice. In one embodiment, there is no TIM between the manifolds andIHS 575 or between the manifolds anddice 520A-520C, respectively. -
FIG. 10 showsinlet 542 connected tomanifold 530A.Inlet 542 is configured to deliver a fluid such as water tomanifold 530A and the distributor assembly therein. The fluid flows through the micro-channels or micro-jets ofdie 520A and into a collector assembly ofmanifold 530A. From the collector assembly, the fluid moves throughoutlet 545A. In this embodiment,outlet 545A also serves as an inlet to theassembly including die 505B and die 520B.Outlet 545A is connected as an inlet tomanifold 530B and fluid flows intomanifold 530B, through the distributor assembly therein and into the micro-channels or micro-jets ofdie 520B and is collected through the collector assembly therein. The collector assembly inmanifold 530B transfers the fluid tooutlet 545B.Outlet 545B, in this embodiment, also serves as the inlet to theassembly including die 505C and die 520C.Outlet 545B delivers fluid tomanifold 530C. The fluid travels through the distributor assembly therein and is collected through the collector assembly and release throughoutlet 550.Outlet 550 is disposed throughIHS 575. - In another aspect, embodiments of the present disclosure are directed to fabrication of a dielectric interface, e.g., as an alternative to interface 140 of
die 105 and die 120 described above inFIG. 1 . -
FIGS. 11A-11D show cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution.FIG. 12 is aflowchart 1200 showing operations in an embodiment of a method of fabricating an assembly offering a thermal solution. - Referring to
FIG. 11A , an active silicon die (or wafer of dies) 1102 and a silicon die (or wafer of dies) 1104 are provided for bonding. The silicon die 1104 has a plurality of fluidlyaccessible channels 1106 therein. Referring tooptional operation 1202 offlowchart 1200, one or both of the active silicon die 1102 and the silicon die 1104 may be subjected to grinding to a target thickness. In other embodiments, the active silicon die 1102 and the silicon die 1104 are not subjected to grinding. In either case, the thickness of each of the active silicon die 1102 and/or the silicon die 1104 may be in a range of approximately 100-800 microns. Referring tooptional operation 1202 offlowchart 1200, one or both of the active silicon die 1102 and the silicon die 1104 may be cleaned, e.g., by wet cleaning and/or plasma cleaning. - Referring to
FIG. 11B and tooperation 1206 offlowchart 1200, afirst dielectric layer 1108 is deposited on a backside of the active silicon die 1102, the backside opposite a device side of the active silicon die 1102. Asecond dielectric layer 1110 may be deposited on thesilicon die 1104. In an embodiment, thefirst dielectric layer 1108 and/or thesecond dielectric layer 1110 are deposited by physical vapor deposition (PVD) or plasma enhanced chemical vapor deposition (PECVD). In an embodiment, one or both of thefirst dielectric layer 1108 and thesecond dielectric layer 1110 is composed of a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx). In an embodiment, each of thefirst dielectric layer 1108 and thesecond dielectric layer 1110 is formed to a thickness in the range of 50-150 nanometers. In an embodiment, both the active silicon die 1102 and the silicon die 1104 have a dielectric layer deposited thereon. In an alternative embodiment, only one of the active silicon die 1102 and the silicon die 1104 has a dielectric layer deposited thereon. - Referring to
operation 1208 offlowchart 1200, an outgassing operation may be performed for one or both of thefirst dielectric layer 1108 and thesecond dielectric layer 1110. In an embodiment, the outgassing operation involves heating to a sufficient temperature to remove trapped gases, such as but not limited to hydrogen or ammonia, in the one or both of thefirst dielectric layer 1108 and thesecond dielectric layer 1110. In one embodiment, the heating is at a temperature less than or equal to 300 degrees Celsius, or more preferably, less than or equal to 200 degrees Celsius. In one embodiment, the heating is at or greater than a temperature used for subsequent bonding (e.g.,operation 1212 of flowchart 1200) of thefirst dielectric layer 1108 and thesecond dielectric layer 1110. In one embodiment, the outgassing densifies thefirst dielectric layer 1108 and/or thesecond dielectric layer 1110. - In an embodiment, the
first dielectric layer 1108 and/or thesecond dielectric layer 1110 are planarized by a chemical mechanical planarization (CMP) process. In one embodiment, thefirst dielectric layer 1108 and/or thesecond dielectric layer 1110 is planarized to a surface roughness less than 0.5 nm Ra (average roughness) or less than 0.5 nm Rq (peak roughness). In an embodiment, thefirst dielectric layer 1108 and/or thesecond dielectric layer 1110 is reduced by a thickness in an amount in the range of 5-50 nanometers during the planarizing. Referring tooperation 1210 offlowchart 1200, thefirst dielectric layer 1108 and thesecond dielectric layer 1110 may be activated and cleaned. In one embodiment, thefirst dielectric layer 1108 and/or thesecond dielectric layer 1110 are exposed to a plasma activation process. In one embodiment, the plasma activation process involves exposing the film to a plasma based on O2, N2, Ar, or a combination thereof, at standard atmospheric pressure and at room temperature. In an embodiment, thefirst dielectric layer 1108 and/or thesecond dielectric layer 1110 are then rinsed with deionized (DI) water or a standard clean is performed. In one embodiment, the surface of both layers is a hydrophillic surface. - Referring to
FIG. 11C and tooperation 1212 offlowchart 1200, thefirst dielectric layer 1108 is contacted to and then bonded to thesecond dielectric layer 1110. The bonding formsinterface dielectric 1108/1110 between the active silicon die (or wafer of dies) 1102 and a silicon die (or wafer of dies) 1104. In an embodiment, contacting thefirst dielectric layer 1108 to thesecond dielectric layer 1110 involves atomic forces between thefirst dielectric layer 1108 and thesecond dielectric layer 1110. In an embodiment, bonding thefirst dielectric layer 1108 to thesecond dielectric layer 1110 involves heating thefirst dielectric layer 1108 and thesecond dielectric layer 1110. In an embodiment, the heating is at a temperature less than or equal to 300 degrees Celsius, or more preferably, less than or equal to 200 degrees Celsius. In an embodiment, the heating is performed at a temperature in the range of 200-300 degrees Celsius. In an embodiment, thedielectric interface 1108/1110 has an interfacial thermal resistance of less than approximately 0.002 C·cm2/W. - Referring to
FIG. 11D , in the case that 1102 and 1104 are wafers of dies, die pairings may be singulated from thewafers first silicon die 1102A having a device side and a backside opposite the device side. A second silicon die 1104A includes a plurality of fluidlyaccessible channels 1106 therein. Adielectric interface 1108/1110 directly couples the second silicon die 1104A to the backside of thefirst silicon die 1102A. The fluidlyaccessible channels 1106 may be coupled to aninlet 1120 and anoutlet 1122, as is depicted. The dicing may provide a same footprint for first silicon die 1102A (active) and the second silicon die 1104A (microchannel die). -
FIGS. 13A-13C show cross-sectional side views of embodiments of an assembly offering a thermal solution. - Referring to
FIG. 13A , adie pairing 1300 includes a first silicon die 1302 having a device side and a backside opposite the device side. A second silicon die 1304 (such as a die having a plurality of fluidly accessible channels therein) is coupled directly to the backside of the first silicon die 1302 by adielectric interface 1306. In an embodiment, thedielectric interface 1306 includes a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx). As illustrated inFIG. 13A , there is no seam within thedielectric interface 1306. In an embodiment, there are no additional thermal interface materials and/or epoxy adhesives between thefirst silicon die 1302 and thesecond silicon die 1304. - Referring to
FIG. 13B , adie pairing 1320 includes a first silicon die 1322 having a device side and a backside opposite the device side. A second silicon die 1324 (such as a die having a plurality of fluidly accessible channels therein) is coupled directly to the backside of the first silicon die 1322 by adielectric interface 1326. In an embodiment, thedielectric interface 1326 includes aseam 1330 therein. In an embodiment, thedielectric interface 1326 is a bilayer having afirst layer 1328A and asecond layer 1328B. In one embodiment, thefirst layer 1328A includes a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx), and thesecond layer 1328B includes a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx). In an embodiment, in the case of a layer of silicon oxide (SiOx), the SiOx is a native oxide on a silicon surface, a grown oxide layer (e.g., thermal oxide), or a deposited layer (e.g., a plasma enhanced chemical vapor deposition, PECVD, layer). - In an embodiment, the
first layer 1328A and thesecond layer 1328B of the bilayer have a same composition. In an embodiment, thefirst layer 1328A and thesecond layer 1328B of the bilayer have a same thickness. In an embodiment, there are no additional thermal interface materials and/or epoxy adhesives between thefirst silicon die 1322 and thesecond silicon die 1324. However, in other embodiments, e.g., where both thefirst layer 1328A and thesecond layer 1328B are silicon nitride (SiN), plasma treatment can create a thin oxide at the interface of thefirst layer 1328A and thesecond layer 1328B in place ofseam 1330 at the location of the dashed line. Similarly, in embodiments where both thefirst layer 1328A and thesecond layer 1328B are silicon carbonitride (SiCN), plasma treatment can create a thin SiCOxNy layer at the interface of thefirst layer 1328A and thesecond layer 1328B in place ofseam 1330 at the location of the dashed line. - In another embodiment, the
first layer 1328A and thesecond layer 1328B of the bilayer have a different composition. In an embodiment, thefirst layer 1328A and thesecond layer 1328B of the bilayer have a different thickness. In an embodiment, there are no additional thermal interface materials and/or epoxy adhesives between thefirst silicon die 1322 and thesecond silicon die 1324. - In an embodiment, one of the
first layer 1328A and thesecond layer 1328B is silicon nitride (SiN) and the other of thefirst layer 1328A and thesecond layer 1328B is silicon carbonitride (SiCN). In an embodiment, one of thefirst layer 1328A and thesecond layer 1328B is silicon nitride (SiN) and the other of thefirst layer 1328A and thesecond layer 1328B is silicon oxide (SiOx). In an embodiment, one of thefirst layer 1328A and thesecond layer 1328B is silicon oxide (SiOx) and the other of thefirst layer 1328A and thesecond layer 1328B is silicon carbonitride (SiCN). - Referring to
FIG. 13C , adie pairing 1340 includes a first silicon die 1342 having a device side and a backside opposite the device side. A second silicon die 1344 (such as a die having a plurality of fluidly accessible channels therein) is coupled directly to the backside of the first silicon die 1342 by adielectric interface 1346. In an embodiment, thedielectric interface 1346 includes aseam 1350 therein. In an embodiment, thedielectric interface 1346 is a bilayer having afirst layer 1348A and asecond layer 1348B. In an embodiment, at least one of thefirst layer 1348A or thesecond layer 1348B of the bilayer is composed of silicon oxide (SiOx) having a plurality ofnanovoids 1352 therein (shown forlayer 1348A in this case, but could instead or in addition be forlayer 1348B). In an embodiment, there are no additional thermal interface materials and/or epoxy adhesives between thefirst silicon die 1342 and thesecond silicon die 1344. -
FIGS. 14A-14D shows cross-sectional side views of operations in an embodiment of a method of fabricating an assembly offering a thermal solution. - Referring to
FIG. 14A , an active silicon die 1404 is provided on asubstrate 1402, such as a package substrate, a silicon interposer, an active interposer (any of which may be in the form of a wafer level package), or a temporary carrier substrate. In the case thatsubstrate 1402 is a package substrate, active silicon die may be flip chip bonded to pads of the package substrate. An underfill material may be between the active silicon die 1404 and thepackage substrate 1402 and along portions of the sidewalls of the active silicon die 1404. The active silicon die 1404 is overmolded with amold compound 1406, as depicted inFIG. 14B . Referring toFIG. 14C , themold compound 1406 is grinded to formmold compound 1406A and to expose the backside of thesilicon die 1404. In one embodiment,mold compound 1406A is on thepackage substrate 1402 and laterally surrounding the first active silicon die 1404. In one embodiment, grinding the mold compound formsconcave regions 1408 in themold compound 1406A. Adielectric layer 1410 is then formed on the backside of the silicon die 1404 and on themold compound 1406A, as is depicted inFIG. 14D . In the case of the formation ofconcave regions 1408, thedielectric layer 1410 may be formed in theconcave regions 1408 in themold compound 1406A. Asecond die 1412 is then bonded to the active silicon die 1404. Thedielectric layer 1410 can be used as a dielectric interface, or a portion of a dielectric interface, between thesecond die 1412 and the active silicon die 1404. In one embodiment, thedielectric layer 1410 is planarized by a chemical mechanical planarization (CMP) process prior to bonding thesecond die 1412 and the active silicon die 1404. In the case thatsubstrate 1402 is a temporary carrier,substrate 1402 may be removed and build-up layers may be formed on the resulting exposed active side of the active silicon die 1404 and on themold compound 1406A, e.g., to provide one or more routing layers having a fan out arrangement. It is to be appreciated that a wafer level package architecture may similarly be fabricated where, e.g., active silicon die 1402 is instead a microchannel die or wafer. In the case that the molded die or wafer includes through silicon vias (TSVs), the above process can be performed before TSV reveal or after TSV reveal. The process may be performed at wafer level and at relatively low temperature. -
FIG. 15 illustrates acomputing device 1500 in accordance with one implementation.Computing device 1500houses board 1502.Board 1502 may include a number of components, including but not limited toprocessor 1504 and at least onecommunication chip 1506.Processor 1504 is physically and electrically coupled toboard 1502. In some implementations at least onecommunication chip 1506 is also physically and electrically coupled toboard 1502. In further implementations,communication chip 1506 is part ofprocessor 1504. - Depending on its applications,
computing device 1500 may include other components that may or may not be physically and electrically coupled toboard 1502. These other components include, but are not limited to, volatile memory (e.g., DRAM), non-volatile memory (e.g., ROM), flash memory, a graphics processor, a digital signal processor, a crypto processor, a chipset, an antenna, a display, a touchscreen display, a touchscreen controller, a battery, an audio codec, a video codec, a power amplifier, a global positioning system (GPS) device, a compass, an accelerometer, a gyroscope, a speaker, a camera, and a mass storage device (such as hard disk drive, compact disk (CD), digital versatile disk (DVD), and so forth). -
Communication chip 1506 enables wireless communications for the transfer of data to and fromcomputing device 1500. The term “wireless” and its derivatives may be used to describe circuits, devices, systems, methods, techniques, communications channels, etc., that may communicate data through the use of modulated electromagnetic radiation through a non-solid medium. The term does not imply that the associated devices do not contain any wires, although in some embodiments they might not.Communication chip 1506 may implement any of a number of wireless standards or protocols, including but not limited to Wi-Fi (IEEE 802.11 family), WiMAX (IEEE 802.16 family), IEEE 802.20, long term evolution (LTE), Ev-DO, HSPA+, HSDPA+, HSUPA+, EDGE, GSM, GPRS, CDMA, TDMA, DECT, Bluetooth, derivatives thereof, as well as any other wireless protocols that are designated as 3G, 4G, 5G, and beyond.Computing device 1500 may include a plurality ofcommunication chips 1506. For instance,first communication chip 1506 may be dedicated to shorter range wireless communications such as Wi-Fi and Bluetooth andsecond communication chip 1506 may be dedicated to longer range wireless communications such as GPS, EDGE, GPRS, CDMA, WiMAX, LTE, Ev-DO, and others. -
Processor 1504 ofcomputing device 1500 includes an integrated circuit die packaged withinprocessor 1504. In some implementations, the integrated circuit die of theprocessor 1504 may include or be part of a thermal solution such as described above. The term “processor” may refer to any device or portion of a device that processes electronic data from registers and/or memory to transform that electronic data into other electronic data that may be stored in registers and/or memory. -
Communication chip 1506 also includes an integrated circuit die packaged withincommunication chip 1506. In accordance with another implementation, the integrated circuit die of thecommunication chip 1506 may include or be part of a thermal solution such as described above. - In further implementations, another component housed within
computing device 1500 may contain an integrated circuit die that may include or be part of a thermal solution such as described above. - In various implementations,
computing device 1500 may be a laptop, a netbook, a notebook, an ultrabook, a smartphone, a tablet, a personal digital assistant (PDA), an ultra mobile PC, a mobile phone, a desktop computer, a server, a printer, a scanner, a monitor, a set-top box, an entertainment control unit, a digital camera, a portable music player, or a digital video recorder. In further implementations,computing device 1500 may be any other electronic device that processes data. - In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiments. It will be apparent however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. The particular embodiments described are not provided to limit the invention but to illustrate it. The scope of the invention is not to be determined by the specific examples provided above but only by the claims below. In other instances, well-known structures, devices, and operations have been shown in block diagram form or without detail in order to avoid obscuring the understanding of the description. Where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.
- It should also be appreciated that reference throughout this specification to “one embodiment”, “an embodiment”, “one or more embodiments”, or “different embodiments”, for example, means that a particular feature may be included in the practice of the invention. Similarly, it should be appreciated that in the description various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects may lie in less than all features of a single disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of the invention.
- Example embodiment 1: An integrated circuit assembly includes a first silicon die comprising a device side and a backside opposite the device side. The integrated circuit assembly also includes a second silicon die comprising a plurality of fluidly accessible channels therein. A dielectric interface directly couples the second silicon die to a backside of the first silicon die.
- Example embodiment 2: The integrated circuit assembly of example embodiment 1, wherein the dielectric interface comprises a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- Example embodiment 3: The integrated circuit assembly of example embodiment 1 or 2, wherein the dielectric interface comprises a seam therein.
- Example embodiment 4: The integrated circuit assembly of example embodiment 1, wherein the dielectric interface is a bilayer having a first layer comprising a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx), and having a second layer comprising a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- Example embodiment 5: The integrated circuit assembly of example embodiment 4, wherein the first layer and the second layer of the bilayer have a same composition.
- Example embodiment 6: The integrated circuit assembly of example embodiment 4, wherein the first layer and the second layer of the bilayer have a different composition.
- Example embodiment 7: The integrated circuit assembly of example embodiment 4, 5 or 6, wherein at least one of the first layer or the second layer of the bilayer comprises silicon oxide (SiOx) having a plurality of nanovoids therein.
- Example embodiment 8: The integrated circuit assembly of example embodiment 1, 2, 3, 4, 5, 6 or 7, further comprising a lid disposed on the second silicon die, the lid comprising an area dimension that covers an area comprising the channels.
- Example embodiment 9: The integrated circuit assembly of example embodiment 8, wherein the lid comprises a fluid inlet and a fluid outlet.
- Example embodiment 10: An integrated circuit assembly includes at least one package including a first silicon die comprising a device side and a backside opposite the device side, a second silicon die coupled directly to the backside of the first silicon die by a dielectric interface, the second silicon die comprising a plurality of channels therein and a fluid inlet operable to deliver a fluid to the plurality of channels and a fluid outlet. The integrated circuit assembly also includes a package substrate coupled to the device side of the first silicon die.
- Example embodiment 11: The integrated circuit assembly of example embodiment 10, wherein the dielectric interface comprises a dielectric material selected from the group consisting of silicon nitride (SiN), silicon carbonitride (SiCN), and silicon oxide (SiOx).
- Example embodiment 12: The integrated circuit assembly of example embodiment 10 or 11, wherein the dielectric interface comprises a seam therein.
- Example embodiment 13: The integrated circuit assembly of example embodiment 10, 11 or 12, wherein the at least one package further comprises a lid disposed on the second die, the lid comprising an area dimension that covers an area comprising the channels.
- Example embodiment 14: The integrated circuit assembly of example embodiment 13, wherein the lid comprises the fluid inlet and the fluid outlet.
- Example embodiment 15: The integrated circuit assembly of example embodiment 10, 11, 12, 13 or 14, further including a mold compound on the package substrate and laterally surrounding the first silicon die.
- Example embodiment 16: The integrated circuit assembly of example embodiment 15, wherein the dielectric interface is further on the mold compound.
- Example embodiment 17: The integrated circuit assembly of example embodiment 15, wherein the mold compound has concave regions therein.
- Example embodiment 18: The integrated circuit assembly of example embodiment 17, wherein the dielectric interface is further in the concave regions of the mold compound.
- Example embodiment 19: A method of fabricating an integrated circuit assembly includes depositing a first dielectric layer on a backside of a first silicon die, the backside opposite a device side of the first silicon die. A second dielectric layer is deposited on a second silicon die, the second silicon die comprising a plurality of fluidly accessible channels therein.
- The first dielectric layer is bonded directly to the second dielectric layer.
- Example embodiment 20: The method of example embodiment 19, wherein depositing the first dielectric layer or the second dielectric layer comprises depositing by physical vapor deposition (PVD) or plasma enhanced chemical vapor deposition (PECVD).
- Example embodiment 21: The method of example embodiment 20, further comprising performing an outgassing process subsequent to depositing by the plasma enhanced chemical vapor deposition (PECVD) and prior to bonding the first dielectric layer directly to the second dielectric layer.
- Example embodiment 22: The method of example embodiment 19, 20 or 21, further including planarizing the first dielectric layer or the second dielectric layer by a chemical mechanical planarization (CMP) process prior to bonding the first dielectric layer directly to the second dielectric layer.
- Example embodiment 23: The method of example embodiment 19, 20, 21 or 22, wherein bonding the first dielectric layer directly to the second dielectric layer comprises exposing the first dielectric layer and the second dielectric layer to a plasma activation process, rinsing the first dielectric layer and the second dielectric layer with deionized (DI) water, contacting the first dielectric layer to the second dielectric layer, and heating the first dielectric layer to the second dielectric layer.
- Example embodiment 24: The method of example embodiment 23, wherein the heating is performed at a temperature in the range of 200-300 degrees Celsius.
- Example embodiment 25: The method of example embodiment 19, 20, 21, 22, 23 or 24, further including, prior to depositing the first dielectric layer on the backside of the first silicon die, overmolding the first silicon die with a mold compound, and grinding the mold compound to expose the backside of the first silicon die, wherein grinding the mold compound comprises forming concave regions in the mold compound. Depositing the first dielectric layer on the backside of the first silicon die further comprises depositing the first dielectric layer on the mold compound and in the concave regions in the mold compound, and the method further includes planarizing the first dielectric layer by a chemical mechanical planarization (CMP) process prior to bonding the first dielectric layer directly to the second dielectric layer.
Claims (25)
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US11470740B2 (en) | 2020-05-29 | 2022-10-11 | Ovh | Uninterruptible power supply having a liquid cooling device |
US11664295B2 (en) * | 2019-05-23 | 2023-05-30 | Ovh | Water block assembly |
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